/*
 * Copyright (c) Hunan Goke,Chengdu Goke,Shandong Goke. 2021. All rights reserved.
 */
#ifndef _DRV_IOCTL_H
#define _DRV_IOCTL_H

/* ioctl command encoding: 32 bits total, command in lower 16 bits,
 * size of the parameter structure in the lower 14 bits of the
 * upper 16 bits.
 * Encoding the size of the parameter structure in the ioctl request
 * is useful for catching programs compiled with old versions
 * and to avoid overwriting user space outside the user buffer area.
 * The highest 2 bits are reserved for indicating the ``access mode''.
 * NOTE: This limits the max parameter size to 16kB -1 !
 */

/*
 * The following is for compatibility across the various Linux
 * platforms.  The generic ioctl numbering scheme doesn't really enforce
 * a type field.  De facto, however, the top 8 bits of the lower 16
 * bits are indeed used as a type field, so we might just as well make
 * this explicit here.  Please be sure to use the decoding macros
 * below from now on.
 */
#define _IOC_NRBITS 8
#define _IOC_TYPEBITS 8

/*
 * Let any architecture override either of the following before
 * including this file.
 */

#ifndef _IOC_SIZEBITS
#define _IOC_SIZEBITS 14
#endif

#ifndef _IOC_DIRBITS
#define _IOC_DIRBITS 2
#endif

#define _IOC_NRMASK ((1 << _IOC_NRBITS) - 1)
#define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS) - 1)
#define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS) - 1)
#define _IOC_DIRMASK ((1 << _IOC_DIRBITS) - 1)

#define _IOC_NRSHIFT 0
#define _IOC_TYPESHIFT (_IOC_NRSHIFT + _IOC_NRBITS)
#define _IOC_SIZESHIFT (_IOC_TYPESHIFT + _IOC_TYPEBITS)
#define _IOC_DIRSHIFT (_IOC_SIZESHIFT + _IOC_SIZEBITS)

/*
 * Direction bits, which any architecture can choose to override
 * before including this file.
 */

#ifndef _IOC_NONE
#define _IOC_NONE 0U
#endif

#ifndef _IOC_WRITE
#define _IOC_WRITE 1U
#endif

#ifndef _IOC_READ
#define _IOC_READ 2U
#endif

#define _IOC(dir, type, nr, size)                                \
	(((dir) << _IOC_DIRSHIFT) | ((type) << _IOC_TYPESHIFT) | \
	 ((nr) << _IOC_NRSHIFT) | ((size) << _IOC_SIZESHIFT))

// #define _IOC_TYPECHECK(t) (sizeof(t))

#ifdef __CHECKER__
#define _IOC_TYPECHECK(t) (sizeof(t))
#else
/* provoke compile error for invalid uses of size argument */
extern unsigned int __invalid_size_argument_for_IOC;
#define _IOC_TYPECHECK(t)                                                  \
	((sizeof(t) == sizeof(t[1]) && sizeof(t) < (1 << _IOC_SIZEBITS)) ? \
		 sizeof(t) :                                               \
		 __invalid_size_argument_for_IOC)
#endif

/* used to create numbers */
#define _IO(type, nr) _IOC(_IOC_NONE, (type), (nr), 0)
#define _IOR(type, nr, size) \
	_IOC(_IOC_READ, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOW(type, nr, size) \
	_IOC(_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOWR(type, nr, size) \
	_IOC(_IOC_READ | _IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOR_BAD(type, nr, size) _IOC(_IOC_READ, (type), (nr), sizeof(size))
#define _IOW_BAD(type, nr, size) _IOC(_IOC_WRITE, (type), (nr), sizeof(size))
#define _IOWR_BAD(type, nr, size) \
	_IOC(_IOC_READ | _IOC_WRITE, (type), (nr), sizeof(size))

/* used to decode ioctl numbers.. */
#define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
#define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
#define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
#define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)

#define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT)
#define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT)
#define IOC_INOUT ((_IOC_WRITE | _IOC_READ) << _IOC_DIRSHIFT)
#define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT)
#define IOCSIZE_SHIFT (_IOC_SIZESHIFT)

#endif /* _DRV_IOCTL_H */
